Direct infant UV light exposure is associated with eczema and immune development

Modifiable risk factors in paediatric atopic dermatitis: is the sun finally shining?

“…give a critical appraisal of a recent RCT examining the effects of vitamin D supplementation in infants . In a post‐hoc analysis, children with high cumulative UVR exposure in the first 3 months of life had a strongly reduced risk of eczema, indicating beneficial effects of the sun that were not explained by vitamin D . This finding is indeed consistent with other studies, but in the comprehensive and detailed analysis of this study, Maslin et al .…”

“…In this issue of the BJD , Maslin et al . give a critical appraisal of a recent RCT examining the effects of vitamin D supplementation in infants . In a post‐hoc analysis, children with high cumulative UVR exposure in the first 3 months of life had a strongly reduced risk of eczema, indicating beneficial effects of the sun that were not explained by vitamin D .…”

Vitamin D is no substitute for the sun

“…In the current issue Rueter et al 5 demonstrate an association between direct UV light exposure in the first 3 months of life and both a decreased incidence of medically diagnosed infant eczema and controlled levels of immune factors associated with allergic inflammation at age 6 months. The authors have reported that greater UV light exposure was associated with decreased PBMC production of IL-2, which contributes to the differentiation of naive CD4 T cells into T H 2 cells, and decreased levels of GM-CSF, which facilitates antigen-specific T H 2 responses and allergic inflammation.…”

“…In summary, Reuter et al 5 report that PBMC production of inflammatory cytokines was lower in those infants who had greater UV light exposure compared with those who had less exposure. It is possible that UV in sunlight initially directly suppresses skin inflammation and then blocks inflammatory cycles that result in systemic inflammation.…”

“…In the current study oral supplementation of vitamin D3 showed no contribution to suppression of allergic symptoms. 5 This might be because the concentration of vitamin D3 in the skin or draining lymph nodes, where lymphocytes are residing and maturating, was insufficient to affect cutaneous lymphocyte-associated antigen reduction.…”